1. Field of the Invention
The present invention relates to a water-proof sealing structure for an electric junction box which is adopted for wiring distribution in a vehicle or the like.
2. Description of the Prior Art
Water-proof sealing structures for an electric junction box have conventionally been constructed as shown in FIGS. 4 to 6, as were proposed in Japanese Utility Model Laid-Open No.1-58983, wherein a packing d or e made of elastomer and rubber respectively (FIG. 6) is attached to a fitting portion c of a water-proof covering which is to be fitted into a main box a, whereas a fitting projection f of the main box a is pushed into the above packing d or e so as to provide a water-proof sealing function due to the suppressing force thereof.
However, as it is required to give a substantially large suppressing force with respect to the fitting projection f and packing d (or e) for securing the water-proofing effect thereof, a locking member composed of a hook portion g and a locking hollow h has to be provided as shown in FIG. 7, which, however, increases the total weight, and cost thereof can be increased. Further, in case a step portion is formed on the fitting portion c of the water-proof covering b because of the condition that the space within the vehicle for mounting the electric junction box is not wide enough to make the fitting portion c in a flat shape, the fitting operation at the step portion can be imperfectly done or the adhesion of the packing is loosened, so that a leakage of water or the like can be thereby caused.